Illegal activity doesn’t appear to be behind the spread of an oyster disease currently affecting southern New Zealand, according to authorities from the country’s Ministry for Primary Industries.
Investigators followed up on several allegations regarding how the oyster disease, Bonamia ostreae, could have arrived in Stewart Island in 2017, including via illegal transfer of spat or possible contamination from French researchers in Marlborough, news outlet Stuff reported.
The parasite, which has spurred mass flat oyster deaths in Europe, was found in May 2017 at marine farms in Big Glory Bay at Stewart Island, located in southern New Zealand. The disease first reached New Zealand in 2015, when it was detected in Marlborough, a central location in the country. Upon discovering the deadly parasite, authorities started issuing controlled-area notices to restrict the movement of oysters and the potential spread of the disease.
Allegations of illegal activity tied to the spread of ostreae in New Zealand’s southern region started surfacing in June 2017, and were compelling enough to drive the ministry to investigate, Stuff reported. The ministry pursued a claim it received surrounding a supposed spat transfer between a Marlborough oyster farm and a Stewart Island farm, which potentially occurred without heeding one of the agency’s controlled-area notices.
After interviewing dozens of people, and looking into whether any breaches of aquaculture regulations had transpired across the region, the ministry concluded it was unlikely that ostreae was spread because of non-compliant activity. Moreover, the ministry said it was unlikely that the parasite arrived naturally through the normal flow of ocean currents.
A national surveillance plan for Bonamia ostreae has been put in place by the ministry in 2018, and will involve wild oysters in the Foveaux Strait being tested every three months, a spokesperson of the agency told Stuff. After speaking with shellfish farmers affected by the parasite, the ministry is also in the process of reviewing several compensation claims, with payments expected to be processed in the near future, officials said.
"MPI met with affected farmers in late 2017 to discuss losses and the compensation process and requirements for submitting and evaluating a claim. MPI is continuing to work with them to action all claims," the ministry’s spokesperson told Stuff.
